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1.
Int J Mol Sci ; 25(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38791398

RESUMO

Chimeric antigen receptor (CAR)-T cell immunotherapy represents a cutting-edge advancement in the landscape of cancer treatment. This innovative therapy has shown exceptional promise in targeting and eradicating malignant tumors, specifically leukemias and lymphomas. However, despite its groundbreaking successes, (CAR)-T cell therapy is not without its challenges. These challenges, particularly pronounced in the treatment of solid tumors, include but are not limited to, the selection of appropriate tumor antigens, managing therapy-related toxicity, overcoming T-cell exhaustion, and addressing the substantial financial costs associated with treatment. Nanomedicine, an interdisciplinary field that merges nanotechnology with medical science, offers novel strategies that could potentially address these limitations. Its application in cancer treatment has already led to significant advancements, including improved specificity in drug targeting, advancements in cancer diagnostics, enhanced imaging techniques, and strategies for long-term cancer prevention. The integration of nanomedicine with (CAR)-T cell therapy could revolutionize the treatment landscape by enhancing the delivery of genes in (CAR)-T cell engineering, reducing systemic toxicity, and alleviating the immunosuppressive effects within the tumor microenvironment. This review aims to explore how far (CAR)-T cell immunotherapy has come alone, and how nanomedicine could strengthen it into the future. Additionally, the review will examine strategies to limit the off-target effects and systemic toxicity associated with (CAR)-T cell therapy, potentially enhancing patient tolerance and treatment outcomes.


Assuntos
Imunoterapia Adotiva , Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/imunologia , Neoplasias/terapia , Neoplasias/imunologia , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/efeitos adversos , Nanotecnologia/métodos , Nanomedicina/métodos , Animais , Microambiente Tumoral/imunologia , Linfócitos T/imunologia , Antígenos de Neoplasias/imunologia
2.
Eur J Pharmacol ; 970: 176508, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38493913

RESUMO

Necroptosis is a pivotal contributor to the pathogenesis of various human diseases, including those affecting the nervous system, cardiovascular system, pulmonary system, and kidneys. Extensive investigations have elucidated the mechanisms and physiological ramifications of necroptosis. Among these, protein phosphorylation emerges as a paramount regulatory process, facilitating the activation or inhibition of specific proteins through the addition of phosphate groups to their corresponding amino acid residues. Currently, the targeting of kinases has gained recognition as a firmly established and efficacious therapeutic approach for diverse diseases, notably cancer. In this comprehensive review, we elucidate the intricate role of phosphorylation in governing key molecular players in the necroptotic pathway. Moreover, we provide an in-depth analysis of recent advancements in the development of kinase inhibitors aimed at modulating necroptosis. Lastly, we deliberate on the prospects and challenges associated with the utilization of kinase inhibitors to modulate necroptotic processes.


Assuntos
Neoplasias , Proteínas Quinases , Humanos , Fosforilação , Proteínas Quinases/metabolismo , Necroptose , Neoplasias/tratamento farmacológico , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Apoptose
5.
Biomedicines ; 11(10)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37893069

RESUMO

This review highlights Receptor Expressed in Lymphoid Tissues (RELT), a Tumor Necrosis Factor Superfamily member, and its two paralogs, RELL1 and RELL2. Collectively, these three proteins are referred to as RELTfms and have gained much interest in recent years due to their association with cancer and other human diseases. A thorough knowledge of their physiological functions, including the ligand for RELT, is lacking, yet emerging evidence implicates RELTfms in a variety of processes including cytokine signaling and pathways that either promote cell death or survival. T cells from mice lacking RELT exhibit increased responses against tumors and increased inflammatory cytokine production, and multiple lines of evidence indicate that RELT may promote an immunosuppressive environment for tumors. The relationship of individual RELTfms in different cancers is not universal however, as evidence indicates that individual RELTfms may be risk factors in certain cancers yet appear to be protective in other cancers. RELTfms are important for a variety of additional processes related to human health including microbial pathogenesis, inflammation, behavior, reproduction, and development. All three proteins have been strongly conserved in all vertebrates, and this review aims to provide a clearer understanding of the current knowledge regarding these interesting proteins.

6.
Int J Mol Sci ; 25(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38203175

RESUMO

The farnesoid-X receptor (FXR), a member of the nuclear hormone receptor superfamily, can be activated by bile acids (BAs). BAs binding to FXR activates BA signaling which is important for maintaining BA homeostasis. FXR is differentially expressed in human organs and exists in immune cells. The dysregulation of FXR is associated with a wide range of diseases including metabolic disorders, inflammatory diseases, immune disorders, and malignant neoplasm. Recent studies have demonstrated that FXR influences tumor cell progression and development through regulating oncogenic and tumor-suppressive pathways, and, moreover, it affects the tumor microenvironment (TME) by modulating TME components. These characteristics provide a new perspective on the FXR-targeted therapeutic strategy in cancer. In this review, we have summarized the recent research data on the functions of FXR in solid tumors and its influence on the TME, and discussed the mechanisms underlying the distinct function of FXR in various types of tumors. Additionally, the impacts on the TME by other BA receptors such as takeda G protein-coupled receptor 5 (TGR5), sphingosine-1-phosphate receptor 2 (S1PR2), and muscarinic receptors (CHRM2 and CHRM3), have been depicted. Finally, the effects of FXR agonists/antagonists in a combination therapy with PD1/PD-L1 immune checkpoint inhibitors and other anti-cancer drugs have been addressed.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Terapia Combinada , Ácidos e Sais Biliares , Homeostase , Inibidores de Checkpoint Imunológico , Microambiente Tumoral , Receptor Muscarínico M3
7.
PLoS One ; 17(5): e0269135, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35622821

RESUMO

Early detection of breast cancer plays a critical role in successful treatment that saves thousands of lives of patients every year. Despite massive clinical data have been collected and stored by healthcare organizations, only a small portion of the data has been used to support decision-making for treatments. In this study, we proposed an engineered up-sampling method (ENUS) for handling imbalanced data to improve predictive performance of machine learning models. Our experiment results showed that when the ratio of the minority to the majority class is less than 20%, training models with ENUS improved the balanced accuracy 3.74%, sensitivity 8.36% and F1 score 3.83%. Our study also identified that XGBoost Tree (XGBTree) using ENUS achieved the best performance with an average balanced accuracy of 97.47% (min = 93%, max = 100%), sensitivity of 97.88% (min = 89% and max = 100%), and F1 score of 96.20% (min = 89.5%, max = 100%) in the validation dataset. Furthermore, our ensemble algorithm identified Cell_Shape and Nuclei as the most important attributes in predicting breast cancer. The finding re-affirms the previous knowledge of the relationship between Cell_Shape, Nuclei, and the grades of breast cancer using a data-driven approach. Finally, our experiment showed that Random Forest and Neural Network models had the least training time. Our study provided a comprehensive comparison of a wide range of machine learning methods in predicting breast cancer risk. It can be used as a tool for healthcare practitioners to effectively detect and treat breast cancer.


Assuntos
Neoplasias da Mama , Algoritmos , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Aprendizado de Máquina , Redes Neurais de Computação
8.
Cancers (Basel) ; 14(6)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35326556

RESUMO

Chimeric antigen receptors (CAR) T cells are T cells engineered to express membrane receptors with high specificity to recognize specific target antigens presented by cancer cells and are co-stimulated with intracellular signals to increase the T cell response. CAR-T cell therapy is emerging as a novel therapeutic approach to improve T cell specificity that will lead to advances in precision medicine. CAR-T cells have had impressive outcomes in hematological malignancies. However, there continue to be significant limitations of these therapeutic responses in targeting solid malignancies such as heterogeneous antigens in solid tumors, tumor immunosuppressive microenvironment, risk of on-target/off-tumor, infiltrating CAR-T cells, immunosuppressive checkpoint molecules, and cytokines. This review paper summarizes recent approaches and innovations through combination therapies of CAR-T cells and other immunotherapy or small molecule drugs to counter the above disadvantages to potentiate the activity of CAR-T cells.

9.
Int J Mol Sci ; 23(4)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35216405

RESUMO

In the United States, breast cancer is among the most frequently diagnosed cancers in women. Breast cancer is classified into four major subtypes: human epidermal growth factor receptor 2 (HER2), Luminal-A, Luminal-B, and Basal-like or triple-negative, based on histopathological criteria including the expression of hormone receptors (estrogen receptor and/or progesterone receptor) and/or HER2. Primary breast cancer treatments can include surgery, radiation therapy, systemic chemotherapy, endocrine therapy, and/or targeted therapy. Endocrine therapy has been shown to be effective in hormone receptor-positive breast cancers and is a common choice for adjuvant therapy. However, due to the aggressive nature of triple-negative breast cancer, targeted therapy is becoming a noteworthy area of research in the search for non-endocrine-targets in breast cancer. In addition to HER2-targeted therapy, other emerging therapies include immunotherapy and targeted therapy against critical checkpoints and/or pathways in cell growth. This review summarizes novel targeted breast cancer treatments and explores the possible implications of combination therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Imunoterapia/métodos , Terapia de Alvo Molecular/métodos , Receptores de Esteroides/metabolismo
10.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070674

RESUMO

BRCA1 and BRCA2 are tumor suppressor genes with pivotal roles in the development of breast and ovarian cancers. These genes are essential for DNA double-strand break repair via homologous recombination (HR), which is a virtually error-free DNA repair mechanism. Following BRCA1 or BRCA2 mutations, HR is compromised, forcing cells to adopt alternative error-prone repair pathways that often result in tumorigenesis. Synthetic lethality refers to cell death caused by simultaneous perturbations of two genes while change of any one of them alone is nonlethal. Therefore, synthetic lethality can be instrumental in identifying new therapeutic targets for BRCA1/2 mutations. PARP is an established synthetic lethal partner of the BRCA genes. Its role is imperative in the single-strand break DNA repair system. Recently, Olaparib (a PARP inhibitor) was approved for treatment of BRCA1/2 breast and ovarian cancer as the first successful synthetic lethality-based therapy, showing considerable success in the development of effective targeted cancer therapeutics. Nevertheless, the possibility of drug resistance to targeted cancer therapy based on synthetic lethality necessitates the development of additional therapeutic options. This literature review addresses cancer predisposition genes, including BRCA1, BRCA2, and PALB2, synthetic lethality in the context of DNA repair machinery, as well as available treatment options.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Predisposição Genética para Doença , Mutações Sintéticas Letais , Neoplasias da Mama/terapia , Reparo do DNA , Feminino , Humanos
11.
J Cancer ; 12(4): 1212-1219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33442419

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy is an innovative form of immunotherapy wherein autologous T-cells are genetically modified to express chimeric receptors encoding an antigen-specific single-chain variable fragment and costimulatory molecules. Moreover, CAR T-cell therapy can only work successfully in patients who have an intact immune system. Therefore, patients receiving cytotoxic chemotherapy will be immunosuppressed making CAR-T therapy less effective. In adoptive CD8+ T-cell therapy (ACT), numerous tumor-specific, engineered T-cells are sourced from patients, expanded in vitro, and infused back expressing tumor-specific antigen receptors. The most successful ACT, anti-CD19 chimeric antigen receptor T-cell therapy directed against B-cell lymphoma, has proved to be efficacious. However, current efforts to utilize this approach for solid tumors, like breast cancer, have shown only modest improvement. Nevertheless, the potential efficacy of CAR-T therapy is promising in an era of immunological advances. By appropriately manipulating CAR T-cells to combat the immunosuppressive forces of the tumor microenvironment, significant eradication of the solid tumor may occur. This review discusses CAR T-cell therapy and its specificity and safety in adoptive cell transfers in breast cancer. We will highlight novel discoveries in CAR T-cell immunotherapy and the formidable barriers including suppression of T-cell function and localization at tumor sites.

12.
Biochem Biophys Rep ; 24: 100868, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33367115

RESUMO

Receptor Expressed in Lymphoid Tissues (RELT) is a human tumor necrosis factor receptor superfamily member (TNFRSF) that is expressed most prominently in cells and tissues of the hematopoietic system. RELL1 and RELL2 are two homologs that physically interact with RELT and co-localize with RELT at the plasma membrane. This study sought to further elucidate the function of RELT by identifying novel protein interactions with RELT family members. The transcription factor MyoD family inhibitor domain-containing (MDFIC) was identified in a yeast two-hybrid genetic screen using RELL1 as bait. MDFIC co-localizes with RELT family members at the plasma membrane; this co-localization was most prominently observed with RELL1 and RELL2. In vitro co-immunoprecipitation (Co-IP) was utilized to demonstrate that MDFIC physically interacts with RELT, RELL1, and RELL2. Co-IP using deletion mutants of MDFIC and RELT identified regions important for physical association between MDFIC and RELT family members and a computational analysis revealed that RELT family members are highly disordered proteins. Immunohistochemistry of normal human lymph nodes revealed RELT staining that was most prominent in macrophages. Interestingly, the level of RELT staining significantly increased progressively in low and high-grade B-cell lymphomas versus normal lymph nodes. RELT co-staining with CD20 was observed in B-cell lymphomas, indicating that RELT is expressed in malignant B cells. Collectively, these results further our understanding of RELT-associated signaling pathways, the protein structure of RELT family members, and provide preliminary evidence indicating an association of RELT with B-cell lymphomas.

13.
PLoS One ; 15(5): e0233672, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469945

RESUMO

Agents that modulate pre-mRNA splicing are of interest in multiple therapeutic areas, including cancer. We report our recent screening results with the application of a cell-based Triple Exon Skipping Luciferase Reporter (TESLR) using a library that is composed of FDA approved drugs, clinical compounds, and mechanistically characterized tool compounds. Confirmatory assays showed that three clinical antitumor therapeutic candidates (milciclib, PF-3758309 and PF-562271) are potent splicing modulators and that these drugs are, in fact, nanomolar inhibitors of multiple kinases involved in the regulation the spliceosome. We also report the identification of new SF3B1 antagonists (sudemycinol C and E) and show that these antagonists can be used to develop a displacement assay for SF3B1 small molecule ligands. These results further support the broad potential for the development of agents that target the spliceosome for the treatment of cancer and other diseases, as well as new avenues for the discovery of new chemotherapeutic agents for a range of diseases.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Éxons/efeitos dos fármacos , Precursores de RNA/genética , Splicing de RNA/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Inibidores de Proteínas Quinases/farmacologia
14.
J Chromatogr A ; 1577: 47-58, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30316615

RESUMO

This study combines a high-performance liquid chromatography-fluorescent detection method (HPLC-FLD) with in-situ cell imaging for the sensitive analysis of glutathione (GSH), cysteine (Cys) and homocysteine (Hcys), using BODIPY®507/545 IA as a labeling reagent. The analytical potential of BODIPY®507/545 IA in cell imaging was deeply explored, concerning fluorescent response, selectivity, cell-permeability, biotoxicity and so on. It is demonstrated that BODIPY®507/545 IA has good biocompatibility and the fluorescence intensity is enhanced remarkably after reacting with thiols. The best derivative condition was obtained in boric acid buffer (0.05 mmol/L, pH 9.5) at 45 °C for 15 min. For chromatographic method, two sensitive methods, HPLC-FLD and capillary electrophoresis-laser-induced fluorescence detection (CE-LIF) were both developed, validated, and compared. The detection limits for the thiols ranged from 5 to 10 nmol/L with HPLC-FLD and 0.5 nmol/L for the CE-LIF method. Finally, HPLC-FLD is adopted to quantify the thiols in HepG2 cell samples after cell imaging.


Assuntos
Cromatografia Líquida de Alta Pressão , Homocisteína/análise , Imagem Óptica , Compostos de Sulfidrila/análise , Compostos de Boro/química , Cisteína/análise , Eletroforese Capilar , Fluorescência , Corantes Fluorescentes/química , Glutationa/análise , Células Hep G2 , Humanos , Limite de Detecção
16.
Bioorg Med Chem Lett ; 27(3): 406-412, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28049589

RESUMO

The splicing of pre-mRNA is a critical process in normal cells and is deregulated in cancer. Compounds that modulate this process have recently been shown to target a specific vulnerability in tumors. We have developed a novel cell-based assay that specifically activates luciferase in cells exposed to SF3B1 targeted compounds, such as sudemycin D6. This assay was used to screen a combined collection of approved drugs and bioactive compounds. This screening approach identified several active hits, the most potent of which were CGP-74514A and aminopurvalanol A, both have been reported to be cyclin-dependent kinases (CDKs) inhibitors. We found that these compounds, and their analogs, show significant cdc2-like kinase (CLK) inhibition and clear structure-activity relationships (SAR) at CLKs. We prepared a set of analogs and were able to 'dial out' the CDK activity and simultaneously developed CLK inhibitors with low nanomolar activity. Thus, we have demonstrated the utility of our exon-skipping assay and identified new molecules that exhibit potency and selectivity for CLK, as well as some structurally related dual CLK/CDK inhibitors.


Assuntos
Quinases Ciclina-Dependentes/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , 2-Aminopurina/análogos & derivados , 2-Aminopurina/química , 2-Aminopurina/metabolismo , Adenina/análogos & derivados , Adenina/química , Adenina/metabolismo , Sítios de Ligação , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Éxons , Genes Reporter , Ensaios de Triagem em Larga Escala , Humanos , Concentração Inibidora 50 , Luciferases/genética , Simulação de Dinâmica Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/metabolismo , Estrutura Terciária de Proteína , Splicing de RNA , Relação Estrutura-Atividade
17.
J Med Chem ; 59(24): 11161-11170, 2016 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-27936709

RESUMO

Here we describe a new approach for tumor targeting in which augmented concentrations of Fe(II) in cancer cells and/or the tumor microenvironment triggers drug release from an Fe(II)-reactive prodrug conjugate. The 1,2,4-trioxolane scaffold developed to enable this approach can in principle be applied to a broad range of cancer therapeutics and is illustrated here with Fe(II)-targeted forms of a microtubule toxin and a duocarmycin-class DNA-alkylating agent. We show that the intrinsic reactivity/toxicity of the duocarmycin analog is masked in the conjugated form and this greatly reduced toxicity in mice. This in turn permitted elevated dosing levels, leading to higher systemic exposure and a significantly improved response in tumor xenograft models. Overall our results suggest that Fe(II)-dependent drug delivery via trioxolane conjugates could have significant utility in expanding the therapeutic index of a range of clinical and preclinical stage cancer chemotherapeutics.


Assuntos
Antineoplásicos/farmacologia , Compostos Ferrosos/farmacologia , Indóis/farmacologia , Pró-Fármacos/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Duocarmicinas , Feminino , Compostos Ferrosos/química , Humanos , Indóis/síntese química , Indóis/química , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Estrutura Molecular , Pró-Fármacos/síntese química , Pró-Fármacos/química , Pirróis/síntese química , Pirróis/química , Pirróis/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
18.
PLoS One ; 11(7): e0157698, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27400197

RESUMO

A new HA/ZrO2-based porous bioceramic artificial vertebral body (AVB), carried a recombinant human bone morphogenetic protein-2 (rhBMP-2)/chitosan slow-release hydrogel was prepared to repair vertebral bone defect in beagles. An ionic cross-linking was used to prepare the chitosan hydrogel (CS gel) as the rhBMP-2 slow-release carrier. The vertebral body defects were implanted with the rhBMP-2-loaded AVB in group A, or a non-drug-loaded AVB in group B, or autologous iliac in group C. The encapsulation rate of rhBMP-2 in rhBMP-2-loaded CS gel was 91.88±1.53%, with a drug load of 39.84±2.34 ng/mg. At 6, 12, 24 weeks postoperatively, radiography showed that the bone calluses gradually increased with time in group A, where the artificial vertebral body had completely fused with host-bone at 24 weeks after surgery. In group C, an apparent bone remodeling was occurred in the early stages, and the graft-bone and host-bone had also fused completely at 24 weeks postoperatively. In group B, fusion occurred less than in groups A and C. At 24 weeks after surgery, micro-computed tomography (Micro-CT) revealed that the volume of newly-formed bone in group A was significantly more than in group B (p<0.05). At 24 weeks after surgery, ultra-compressive strengths of the operated segments were 14.03±1.66 MPa in group A, 8.62±1.24 MPa in group B, and 13.78±1.43 MPa in group C. Groups A and C were both significantly higher than group B (p < 0.05). At 24 weeks postoperatively, the hard tissue sections showed that the AVB of group A had tightly fused with host bone, and that pores of the AVB had been filled with abundant nearly mature bone, and that the new bone structured similarly to a trabecular framework, which was similar to that in group C. In contrast, implant fusion of the AVB in group B was not as apparent as group A. In conclusion, the novel HA/ZrO2-based porous bioceramic AVB carried the rhBMP-2-loaded CS gel can promote the repair of bony defect, and induce bone tissue to grow into the pores, which may replace iliac bone grafts as commonly applied in clinical practice.


Assuntos
Proteína Morfogenética Óssea 2/química , Cerâmica/química , Quitosana/química , Durapatita/química , Hidrogéis/química , Coluna Vertebral , Fator de Crescimento Transformador beta/química , Zircônio/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Fenômenos Biomecânicos , Proteína Morfogenética Óssea 2/farmacologia , Preparações de Ação Retardada , Cães , Portadores de Fármacos/química , Humanos , Imageamento Tridimensional , Masculino , Osteogênese/efeitos dos fármacos , Porosidade , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiologia , Fator de Crescimento Transformador beta/farmacologia , Microtomografia por Raio-X
19.
J Ethnopharmacol ; 187: 28-41, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27085942

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Acupuncture is a key part of traditional Chinese medicine, shown to induce favorable neuroplasticity for injuries in the central and peripheral nervous systems. Recent studies report elongated needle therapy (ENT) with BL54 and ST28 may restore acute spinal cord injury (ASCI). However, the precise mechanism for this has not been elucidated. AIM OF THE STUDY: In our current study, we investigated the effects of ENT on inflammation and neuronal apoptosis induced by ASCI, and whether PI3K/Akt and MAPK/ERK signaling pathways are involved in the ENT restoration effect. MATERIALS AND METHODS: Rat models of moderate SCI were established in accordance with the modified Allen's method and were treated with ENT continuously for 7 days. Spontaneous activities were evaluated by the Basso Beattie and Bresnahan locomotor scale. Levels of inflammatory cytokines, such as tumor necrosis factor alpha, interleukin-6, IL-1ß, and nuclear factor kappa-ß, were determined by enzyme-linked immunosorbent assay. Cell apoptosis was examined by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The proportions of cells with positive Bcl-2 and Bax expression were determined by immunohistochemical assays, whilst the expression profiles of p-AKT and p-ERK in spinal cord tissues were evaluated by western blotting. Furthermore, the expression profiles of Cytochrome-C (Cyt-C) and caspase-3 in vivo were analyzed by reverse transcription polymerase chain reaction. The potential inhibitory effects downstream of the Akt and ERK signaling pathways were examined by administration of specific inhibitors LY294002 and PD98059 in vivo. RESULTS: As indicated by this study, inflammation as well as PI3K/Akt- and MAPK/ERK signaling pathway-mediated neuronal apoptosis were involved in the course of SCI in rats. The neuro-protective effect of ENT was associated with reduced Bax protein-positive neurons and increased Bcl-2 protein-positive neurons. ENT enhanced recovery of rat activities. Activation of p-Akt and p-ERK in the PI3K/Akt and MAPK/ERK signaling pathways, inhibited expression of the critical component Cyt-C. Cyt-C is required for the mitochondrial apoptosis pathway and cascade of caspase-3, which is involved in activation of neuronal apoptosis through down-regulation of Bax protein and up-regulation of Bcl-2, as determined by TUNEL. The administration of PI3K/Akt and MAPK/ERK signaling pathway specific inhibitors, LY294002 and PD98059, suppressed expression of both p-Akt and p-ERK. CONCLUSION: ENT with BL54 and ST28 points can promote the recovery of ASCI. And the neuro-protective effect of ENT during the restoration of SCI may be associated with the suppression of both inflammation and activation of PI3K/Akt and MAPK/ERK signaling pathways, resulting from down-regulation of Bax protein, up-regulation of Bcl-2, and inhibition of the mitochondrial apoptosis pathway.


Assuntos
Terapia por Acupuntura , Medicina Tradicional Chinesa , Agulhas , Traumatismos da Medula Espinal/terapia , Animais , Caspase 3/genética , Cromonas/farmacologia , Citocromos c/genética , Citocinas/metabolismo , Flavonoides/farmacologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Morfolinas/farmacologia , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismo , Proteína X Associada a bcl-2/metabolismo
20.
J Biol Chem ; 290(46): 27460-72, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26324718

RESUMO

Depletion of inositol has profound effects on cell function and has been implicated in the therapeutic effects of drugs used to treat epilepsy and bipolar disorder. We have previously shown that the anticonvulsant drug valproate (VPA) depletes inositol by inhibiting myo-inositol-3-phosphate synthase, the enzyme that catalyzes the first and rate-limiting step of inositol biosynthesis. To elucidate the cellular consequences of inositol depletion, we screened the yeast deletion collection for VPA-sensitive mutants and identified mutants in vacuolar sorting and the vacuolar ATPase (V-ATPase). Inositol depletion caused by starvation of ino1Δ cells perturbed the vacuolar structure and decreased V-ATPase activity and proton pumping in isolated vacuolar vesicles. VPA compromised the dynamics of phosphatidylinositol 3,5-bisphosphate (PI3,5P2) and greatly reduced V-ATPase proton transport in inositol-deprived wild-type cells. Osmotic stress, known to increase PI3,5P2 levels, did not restore PI3,5P2 homeostasis nor did it induce vacuolar fragmentation in VPA-treated cells, suggesting that perturbation of the V-ATPase is a consequence of altered PI3,5P2 homeostasis under inositol-limiting conditions. This study is the first to demonstrate that inositol depletion caused by starvation of an inositol synthesis mutant or by the inositol-depleting drug VPA leads to perturbation of the V-ATPase.


Assuntos
Anticonvulsivantes/farmacologia , Inositol/deficiência , Liases Intramoleculares/antagonistas & inibidores , ATPases Vacuolares Próton-Translocadoras/metabolismo , Vacúolos/enzimologia , Ácido Valproico/farmacologia , Farmacorresistência Fúngica/genética , Deleção de Genes , Homeostase , Inositol/genética , Mio-Inositol-1-Fosfato Sintase/genética , Pressão Osmótica , Fosfatos de Fosfatidilinositol/metabolismo , Transporte Proteico , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , ATPases Vacuolares Próton-Translocadoras/genética
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